Boring type continuous miner having three boring heads and method of mining



J. KARLOVSKY, JR

Dec. 27, 1966 BORING TYPE CONTINUOUS MINER HAVING THREE BORING HEADS AND METHOD OF MINING 2 Sheets-Sheet 1 Filed Dec. 2, 1965 m m; I w u 3 H mm J 0 w M T K 3 h E P w 1966 J. KARLOVSKY, JR 3,294,450

BORING TYPE CONTINUOUS MINER HAVING THREE BORING HEADS AND METHOD OF MINING INVENTOR. JERRY KARLovsx-Y, E.

J BY s d/gg United States Patent ()fiice 3,294,45d Patented Dec. 2?, 1966 EQRHNG TYPE CONTINUOUS MINER MA /ENG THREE EGRING HEADS AND METHOD OF MENENG Jerry Karim sky, Jr., Nashville, IlL, assignor to National Mine Service Company, Pittsburgh, Pa, a corporation of West Virginia Filed Dec. 2, 1963, Ser. No. 327,466 6 Claims. (Cl. 2299-48) This invention relates to improvements in continuous mining machines of the boring type and more particularly to an improved boring type mining machine that has three rotary boring heads arranged to bore three overlapping bores in the mine face.

Among the many types of machines used to continuously remove coal and other materials from a seam or vein, there is a boring type mining machine generally designated as the McKinlay entry driver. This machine has a frame mounted on endless type treads that permits the machineto tram or continuously advance int-o the mine face as the material is dislodged therefrom. The frame is so constructed that the dislodged material is conveyed rearwardly by a longitudinally extending conveyor. The McKinlay type machine has a pair of spaced rotatable drive shafts extending forwardly from the front end of the frame and rotatable boring or cutting heads secured to the drive shafts. The boring heads rotate in a plane parallel to the mine face and have arms extending radially therefrom with cutter bits secured to forwardly extending supports on the arms. As the mining machine advances into the face, the cutter bits attack the face and cut overlapping bores to form an elongated entry in the mine face.

One of the difficulties encountered with the two-borer McKinlay type mining machine is the limitations in the width of the entry that can be made by the overlapping bores formed in the mine face. If the boring heads are spaced so that the bores formed in the mine face are not overlapping, a vertical rib of material projects rearwardly from the mine face between the two bores formed by the rotary boring heads. Considerable difliculty is encountered in removing the rearwardly projecting vertical rib which reduces substantially the rate at which the continuous mining machine advances into the face and dislodges material therefrom.

Under certain mining conditions it is'highly desirable to increase the width of the entry that can be formed in the face by the continuous mining machine. By increasing the width of the entry and maintaining the mining machine rate of advance into the mine face substantially the same, it is possible to increase the tonnage of material dislodged from the face in a given period of time. Thus, by boring wider entries in the mine face it is possible to increase overall rate of material removal.

It has been discovered by spacing the rotary boring heads so that the bores formed thereby are in spaced relation and providing a third or intermediate boring head therebetween positioned in a plane other than the vertical plane of the pair of end boring heads that it is possible to out three overlapping bores in the mine face. A pair of upper and lower trimming cutters are arranged to form substantially horizontal linear kerfs tangential with the bores formed by the pair of end boring heads. The intermediate boring head is of a radial dimension smaller than the pair of end boring heads and two rearwardly projecting cusps of material are formed in the mine face. Associated with the trimming cutters are wedge type dislodging means that continuously dislodge and remove the rearwardly projecting upper and lower cusps formed in the material as the mining machine advances into the mine face.

Accordingly, the principal object of this invention is to provide a boring tye mining machine having a pair of spaced end boring heads and an intermediate boring head positioned therebetween.

Another object of this invention is to provide a boring type mining machine having a pair of spaced rotary boring heads arranged for rotation in a first vertical plane and an intermediate rotary boring head arranged for rotation in a different vertical plane.

A further object of this invention is to provide a boring type mining machine having a pair of end rotary boring heads, an intermediate rotary boring head positioned therebetween having a radial dimension smaller than the pair of end rotary boring heads, and a pair of upper and lower substantially horizontal trimmer cutters.

These and other objects of this invention will be more completely disclosed and described in the following specification, the accompanying drawings and the appended claims.

In the drawings:

FIGURE 1 is a front end view of a continuous mining machine of the boring type constructed in accordance with the principles of the present invention having portions of the cusps broken away to illustrate the wedge type breaker means.

FIGURE 2 is a fragmentary elevational view in section taken along the line 22 in FIGURE 1 illustrating the manner in which the intermediate rotary cutting head forms a central bore in the rearward projection of material formed by the pair of end boring heads and the manner in which the cusps are dislodged.

FIGURE 3 is a fragmentary top plan view of the continuous mining machine illustrating the arrangement of the boring heads.

FIGURE 4 is a fragmentary view in elevation illustrating the general arrangement of the boring heads in elevation.

The boring type continuous mining machine illustrated in FIGURES 1-4 has a frame 10 that is mounted on endless treads (not shown) so that the machine can continuously advance as the material is removed from the mine face. The frame 10 carries suitable propelling means for the mining machine and suitable means to rotate the boring heads extending forwardly therefrom. The frame 10, propelling means and drive means are conventional and do not form a part of this invention. Suitable propelling means and rotating means are pres- Bntly utilized in the type 675 continuous miner manufactured and sold by National Mine Service Company, the assignee of the present invention.

Extending forwardly from the frame 10 are three rotatable drive shafts 12, 14 and 16 that are arranged in substantially the same horizontal plane, as is illustrated in FIGURE 1. The shafts 12 and 16 have secured thereto for rotation therewith rotary boring heads 18 and 20. The rotary boring heads 18 and 20 are similar in construction andeach has three arms 22, 24 and 26 extending radially therefrom. The arms 22, 24 and 26 have extensible portions 28 positioned thereon and movable radially relative thereto. The extensible portions 28 have forwardly extending bit supports 30 and 32. Cutter bits 34 and 36 are secured to the front portions of the bit supports 30 and 32 and are arranged to cut annular kerfs in the mine face. Suitable breaker or dislodging means may be provided on the supports 30 and 32 to dislodge the annular cusps of material remaining between the annular kerfs formed by cutter bits 34 and 36. Extending axially from the arms 18 and 20 are cylindrical core bursters 38 which have cutter bits 40 extending forwardly from their front end portions. The core bursters 38 have means provided to remove the central core of material entering the inner portion thereof and may be provided with wedge type breaker means to dislodge the annular rearward projection of material formed by the bits 36 and 40. Although three-arm rotary cutter heads 18 and 20 are described, it should be understood that boring heads having other configurations could be also utilized. Any configuration of rotary boring head that cuts a horizontal bore into the mine face, such as a two-arm boring head or the like, can be used in practicing the invention herein described.

The extensible portions 28 on arms 22, 24 and 26 of both rotary boring heads 18 and 20 have plow means 42 which are arranged to direct the flow of material toward the center of the mining machine. As illustrated in FIGURE 1, the rotary boring head 18 rotates in a counterclockwise direction and rotary boring head 20 rotates in a clockwise direction. With this arrangement the plow means 42 directs the material dislodged by the boring heads 18 and 20 toward the center of the machine where it is picked up on a centrally located longitudinal conveyor 44 (FIGURE 3) and conveyed rearwardly through a throat section 46 in frame to a receiving means positioned behind the mining machine.

The intermediate shaft 14 has secured thereto a rotary boring head 48 that has three arms 50, 52 and 54- extendin g radially therefrom. Extending forwardly from the arms 50, 52 and 54 are cutter bits supports 56 that have cutter bits 58 secured thereto. The cutter bits 58 are arranged to cut an annular kerf in the intermediate portion of the mine face. An axial core burster 60 extends forwardly from the rotary boring head 48 and has cutter bits 62 secured to its front end portion. The cutter bits 58 and 62 are arranged to cut a pair of annular kerfs in the intermediate portion of the mine face between the pair of bores formed between end boring heads 18 and 20. Suitable burster means may be provided on the arms 50, 52 and 54 and core burster 60 to dislodge the annular projection of material between the cutter bit supports 56 and core burster 60. Suitable means may be provided within the inner portion of core burster 60 to dislodge the rearwardly extending cylindrical projection of material formed by the bits 62 on the front end of core burster 60. Suitable plow means 63 are provided on arms 50, '52, and 54 to convey the material dislodged away from the mine face. Thus the intermediate rotary boring head 48 cuts a bore in the intermediate portion of the mine face. The dimension of the intermediate rotary boring head 48 and the pair of end boring heads 18 and 20 is such that the bores formed by the boring heads 18, 48 and 20 overlap. It should be understood that the intermediate boring head can have other configurations as long as the material dislodged by the intermediate cutter head is free to enter the throat portion of the conveying means.

The frame 10 has a top cutter bar trimmer 64 that is adjustable in a vertical direction and has a guideway 66 for an endless cutter chain 68. Similarly the frame has secured thereto a :bottom cutter bar 70 with a suitable guide 72 for the endless chain 68. The lower cutter bar 70 is also adjustable in a vertical direction. The endless cutter chain 68 is guided through guideways 66 and 72 and is driven by suitable sprocket means, as is well known in the art. The endless chain 68 has cutter bits 74 extending forwardly therefrom and arranged to cut horizontal kerfs in the mine face substantially tangential to the bores formed by the end rotary boring heads 18 and 20.

The cutter bar 64 has depending therefrom a plurality of wedge type breaker means 76 which are arranged to dislodge the upper cusps of unmined material remaining after the boring heads 18, 48 and 20 have formed the three overlapping bores in the mine face. Similarly, the lower cutter bar 70 has a plurality of wedge members 78 extending upwardly therefrom and arranged to dislodge the lower cusp of material remaining after the 4 rotary boring heads 18, 48 and 20 have formed overlapping bores in the mine face.

The rotary boring heads 18 and 20 are positioned for rotation in substantially the same vertical plane forwardly of the frame 10 (FIGURE 3). The intermediate rotary cutter head 48 is positioned for rotation in a vertical plane spaced rearwardly of the pair of end rotary cutters 18 and 20 as is illustrated in FIGURES 2 and 3. With this arrangement the pair of end rotary boring heads 18 and 20 first cut a pair of bores into the mine face and form an intermediate rearwardly extending projection of unmined material designated 80 in FIGURE 3. The intermediate boring head 48 thereafter forms an annular bore in the intermediate rearward projection of unmined material 80. Because of the radial dimensions of the boring heads 18, 20 and 48, the intermediate bore formed by boring head 48 overlaps the bores formed by the pair of end boring heads 18 so that upper and lower cusps generally designated by the numerals 82 and 84 in FIGURES 1 and 2 remain unmined. The cutter chain 68 is guided in the guideways 66 of top cutter 64 and the guideway 72 in bottom trimming cutter 70 in a vertical plane spaced rearwardly of the cutter bits on the intermediate rotary boring head 48. The top cutter 64 and bottom cutter 70 form horizontal linear kerfs generally designated by the numerals 86 and 88 in the cusps 82 and 84 after the intermediate rotary boring head 48 has formed an intermediate bore in the rearward projection 80. The wedge devices 76 and 78 exert downward and upward forces on the cusps 82 and 84 respectively to break and dislodge the cusps 82 and 84 as the mining machine advances into the mine face. With the arrangement herein described it is now possible to form an entry of increased lateral dimension in the mine face and increase the rate of production of the mining machine.

According to the provisions of the patent statutes, I have explained the principle, preferred construction and mode of operation of my invention, and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. In a continuous mining machine the combination comprising,

a frame having a centrally located throat opening at the lower front end thereof,

a longitudinal conveyor extending rearwardly on said frame from the centrally located throat opening, said conveyor arranged to convey the material dislodged rearwardly on said frame,

a pair of end boring heads and an intermediate boring head rotatably mounted on said frame and extending forwardly therefrom, said intermediate boring head having a diameter less than the diameter of said pair of end boring heads,

said boring heads arranged to out three overlapping bores in a mine face in advance of said frame,

said pair of boring heads positioned for rotation in substantially the same vertical plane,

said pair of end boring heads arranged to dislodge material from the mine face in substantially the same vertical plane and arranged to rotate in opposite directions and convey material dislodged thereby toward said centrally located throat opening, and

said intermediate boring head positioned for rotation in a vertical plane between said pair of end boring heads and said frame and in a vertical plane rearwardly of said vertical plane of said pair of end boring heads,

said pair of end boring heads arranged to first form a pair of circular bores in the mine face and form a rearwardly extending intermediate projection of material therebetween,

said intermediate boring head arranged to thereafter form a circular bore in said rearwardly extending intermediate projection of a diameter smaller than the diameter of the bores formed by said pair of end boring heads,

said circular bore in said intermediate projection overlapping said pair of circular bores formed by said pair of end boring heads.

2. In a continuous mining machine the combination comprising,

a frame having a centrally located throat opening at the lower front end thereof,

a longitudinal conveyor extending rearwardly on said frame from the centrally located throat opening, said conveyor arranged to convey the material dislodged rearwardly on said frame,

three rotatable shafts extending forwardly from said frame,

said shafts arranged in substantially the same horizontal plane,

a pair of end boring heads and an intermediate boring head secured to said respective shafts for rotation therewith,

said intermediate boring head having a diameter less than the diameter of said pair of end boring heads,

said pair of end boring heads positioned for rotation in substantially the same vertical plane so that said pair of end boring heads dislodge material from the mine face in substantially the same vertical plane and rotate in opposite directions to convey dislodged material towards said centrally located throat opening, and

said center boring head positioned for rotation in a vertical plane between said pair of end boring heads and said frame so that said pair of end boring heads first form a pair of circular bores in the mine face and form a rearwardly extending intermediate projection of material therebetween,

said intermediate boring head arranged to thereafter form a circular bore in said rearwardly extending intermediate projection of a diameter smaller than the diameter of the bores formed by said pair of end boring heads,

said circular bore in said rearwardly extending intermediate projection overlapping said pair of circular bores formed by said end boring heads.

3. In a continuous mining machine the combination comprising,

a frame having a centrally located throat opening at the lower front end thereof,

a longitudinal conveyor extending rearwardly on said frame from the centrally located throat opening, said conveyor arranged to convey the material dislodged rearwardly on said frame,

a pair of end boring heads and an intermediate boring head mounted on said frame and arranged to rotate about parallel axes,

said rotary boring head axes arranged in substantially the same horizontal plane,

said boring heads arranged to cut three overlapping bores in a mine face in advance of said frame,

said pair of end boring heads positioned for rotation in substantially the same vertical plane and in opposite directions so that said pair of boring heads dislodge material from the mine face in substantially the same vertical plane and convey the dislodged material towards said centrally located throat p g,

said intermediate boring head positioned for rotation in a vertical plane between said pair of end boring heads and said frame so that the pair of end boring heads first form a pair of circular bores in the mine face and form a rearwardly extending intermediate projection of material therebetween,

said intermediate boring head having a radial dimension smaller than said pair of end boring heads to thereby form an intermediate bore of smaller dimension than the bores formed by said pair of end boring heads in the rearwardly extending intermediate projection of material between the pair of circular end bores formed by said pair of end boring heads,

said intermediate boring head arranged to form a circular bore in said rearwardly extending intermediate projection of material formed between said circular bores formed by said pair of end boring heads,

an upper trimming cutter secured to said frame and operable to cut an upper linear kerf substantially tangential to the upper portions of the end bores formed by said pair of end boring heads,

a lower trimming cutter secured to said frame and operable to cut a linear lower kerf substantially tangential to the lower portions of said end bores formed by said end pair of boring heads, and

means to dislodge the cusps of material formed between said intermediate boring head and said upper and lower trimming cutters.

4. A continuous mining machine as set forth in claim 3 in which said upper and lower trimming cutters are arranged in a vertical plane spaced rearwardly of said pair of end boring heads.

5. A continuous mining machine as set forth in claim 3 in which said trimming cutters include an endless cutter chain having an upper run to form said upper trimming cutter and a lower run to form said lower trimming cutter.

6. A method of continuous mining with a continuous miner having a pair of spaced end rotary boring heads, an intermediate rotary boring head, and upper and lower trimming cutters which includes the steps of:

first forming a pair of spaced end bores in the mine face with a rearwardly extending projections of material there between,

thereafter forming an intermediate bore in said rearwardly extending projection of material that overlaps said pair of end bores and forms upper and lower cusps in said rearwardly extending projection,

forming a pair of substantially horizontal kerfs in said rearwardly extending projection of material,

said horizontal kerfs extending substantially tangentially to the upper and lower portions of said pair of spaced end bores, and

dislodging the cusps of material formed between said horizontal kerfs and said intermediate bore.

References Cited by the Examiner UNITED STATES PATENTS 2,743,092 4/1956 Funk 299- X 2,750,175 6/1956 Cartlidge 299-57 2,801,091 7/1957 Joy 299-56 3,140,121 7/1964 Gonski 299-57 FOREIGN PATENTS 59,095 4/1954 France. 1,198,314 12/1959 France.

ERNEST R. PURSER, Primary Examiner, 

6. A METHOD OF CONTINUOUS MINING WITH A CONTINUOUS MINER HAVING A PAIR OF SPACED END ROTARY BORING HEADS, AN INTERMEDIATE ROTARY BORING HEAD, AND UPPER AND LOWER TRIMMING CUTTERS WHICH INCLUDES THE STEPS OF: FIRST FORMING A PAIR OF SPACED END BORES IN THE MINE FACE WITH A REARWADLY EXTENDING PORJECTIONS OF MATERIAL THERE BETWEEN, THEREAFTER FORMING AN INTERMEDIATE BORE IN SAID REARWARDLY EXTENDING PROJECTION OF MATERIAL THAT OVERLAPS SAID PAIR OF END BORES AND FORMS UPPER AND LOWER CUSPS IN SAID REARWADLY EXTENDING PROJECTION, FORMING A PAIR OF SUBSTANTIALLY HORIZONTAL KERFS IN SAID REARWARDLY EXTENDING PROJECTION OF MATERIAL, SAID HORIZONTAL KERFS EXTENDING SUBSTANTIALLY TANGENTIALLY TO THE UPPER AND LOWER PORTIONS OF SAID PAIR OF SPACED END BORES AND DISLODGING THE CUSPS OF MATERIAL FORMED BETWEEN SAID HORIZONTAL KERFS AND SAID INTERMEDIATE BORE. 